Rookie Michael Morgan looks likely to get the first shot at the North Queensland halfback spot alongside superstar Johnathan Thurston this NRL season after a dominant performance in the Cowboys' last-minute 28-22 trial win over St George Illawarra.

With many of their major playmakers missing, including Thurston, Morgan scored the game's second try and was the standout for the Cowboys at Barlow Park in Cairns.

Locked in a three-way battle with Ray Thompson and Robert Lui for the No.7 jersey, Thompson impressed in North Queensland's run to the finals last year and has begun the new season in form.

In front of a solid crowd of 12,036, the Cowboys put a tumultuous week behind them to snatch the late win, despite missing Kangaroos playmaker Thurston with a hand injury.

English recruit Scott Moore was another who impressed for North Queensland as he looks to fill the vacant hooking spot at Townsville following the requirement of Aaron Payne.

Captain Matt Scott, who re-signed for the Cowboys mid-week for a further four years, was particularly impressed with Moore.

"He was very sharp out of dummy half, he took the line on a few times, it's probably something we've been lacking recently," he said.

The Cowboys led 18-4 early after tries to ex-Dragons fullback Clint Greenshields, in his first outing for North Queensland, Morgan and Jason Taumalolo were matched by a four-pointer to Chase Stanley for the visitors.

Former representative centre Matt Cooper scored just before halftime to have the Dragons trailing 18-10.

St George Illawarra playmaker Jamie Soward crossed in the 53rd minute and the visitors snatched the lead 22-18 when back-rower Bronson Harrison scored in the final quarter. Before Matt Bowen's teenage nephew Javid scored late to tie the scores at 22-all and Joel Riethmuller crossed for the matchwinner.

Replacement halfback Josh Drinkwater showed some good signs for the Dragons when he came on in the second half and has given coach Steve Price plenty to think about going into next weekend's Charity Shield game.

"(He) showed some really good glimpses out there with the opportunities he got in the second half, so it was quite promising on Josh's display to get an opportunity to make his first grade debut," he said.

Gerard Beale was solid at the back and Soward was prominent.

Cowboys coach Neil Henry said he was likely to play most of his big guns in their final trial against Gold Coast next week.

"JT should be there, I think Brett Tate, Matty Bowen, they're the guys that all had the shoulder operations a bit later so we're expecting them to play, Ash Graham should be able to play as well," he said.